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29
EN
Welding inverters allow TIG welding with touch-triggering. The TIG method
is very effective for welding stainless steel. Switch the machine to TIG mode.
Connecting the welding torch and the cable:
Connect the welding torch to the minus pole and the ground wire to the
plus pole - direct polarity.
Selection and preparation of tungsten electrodes:
Table 1 shows the welding current and diameter values for tungsten
electrodes with 2% thoria - red electrode markings.
Table 1
Diameter of the Electrode (mm)
Welding Current (A)
1.0
15 - 75
1.6
60 - 150
2.4
130 - 240
Prepare the tungsten electrode according to the values in Table 2 and
Picture 3.
Picture 3
α
Table 2
α (°)
Welding current (A)
30
0 - 30
60 - 90
30 - 120
90 - 120
120 - 250
Grinding of tungsten electrodes:
By proper choice of the tungsten electrode and its preparation will affect
the properties of the welding arc, weld geometry and electrode life. The
electrode must be gently grinded in the longitudinal direction as shown in
Figure 4. Figure 5 shows the effect of grinding the electrode on its service
life.
Picture 4
Picture 5
Figure 5A -
Fine and even grinding of the electrode in the longitudinal
direction - Lifetime up to 17 hours
Figure 5B -
Coarse and uneven grinding in the transverse direction - Lifetime
5 hours
A B
Parameters to compare the influence of the electrode grinding method are
given using:
HF ignition el. arc, electrodes Ø 3.2 mm, welding current 150 A and welded
materiál - pipe.
Protective gas:
For TIG welding, it is necessary to use argon with a purity of 99.99 %. Deter-
mine the amount of flow according to Table 3.
Table 3
Welding current
(A)
Diameter of
electrode
(mm)
Welding nozzle
Flow of
gas
(l/min)
n (°)
Ø (mm)
6 - 70
1.0
4/5
6/8,0
5 - 6
60 - 140
1.6
4/5/6
6.5/8.0/9.5
6 - 7
120 - 240
2.4
6/7
9.5/11.0
7 - 8
Holding the welding torch during welding:
90°
45°
Position W (PA)
Position H (PB)
10 – 30°
15 – 40°
Position S (PF)
10
-
30°
20 - 30°
Position S (PF)
Preparation of basic material:
Table 4 lists the material preparation values. Dimensions are determined
according to pic. 6.
Picture 6
a
s
α
d
1
2
3
4
5
6
7
1-3 mm
1-3 mm
1-3 mm
8-10 mm
0 - 5 s
POST GAS
I
0
ON
IW
I
START
I
END
Picture 2 - welding process at TIG LA
